Paper machine headbox with adjustable slice



Jan. 26, 1965 L. A. MOORE 3,167,470

PAPER MACHINE HEADBOX WITH ADJUSTABLE SLICE Filed March 17, 1961 2Sheets-Sheet l IN VEN TOR.

LAWRENCE A. MOORE wwwwf ATTORNEYS Jan. 26, 1965 1.. A. MOORE 3,167,470

PAPER MACHINE HEADBOX WITH ADJUSTABLE SLICE Filed March 17, 1961 2Sheets-Sheet 2 INVEN TOR. LAWRENCE A. MOORE ATTORNEYS if x s,1e7,470PAPER MACHINE HEADBOX WlTH ADJUSTABLE SLECE Lawrence A. Moore, Beloit,Wis, assignor to The Black- Clawson Qompany, Hamilton, Ohio, acorporation of Shin Filed 17, 1961, Ser. No. 96,503 4 Claims. (Cl.162-347) This invention relates to paper making machines, and moreparticularly to a headbox for a Fourdrinier paper machine.

The invention is directed to the provision of a headbox for use incombination with a Fourdrinier paper machine capable of operating over arange of wire speeds which includes very high speeds requiring a highspouting velocity of the stock and correspondingly high pre sureeffective on the stock within the headbox. The invention is especiallyconcerned with the provision of a headbox structure which is capable ofdelivering stock to the forming wire at high velocity and a highvolumetric rate of fiow and also with an accurately controlled flowacross the entire width or" the wire in all adjusted positions of theslice opening.

It is a primary object of the invention to provide a headbox for thepurposes outlined above wherein the upper slice lip is of novelconstruction providing for adjustment in both vertical and horizontaldirections and wherein each rectifier roll mounted adjacent the slicelip is equipped with adjustable mountings of novel construction assuringthat it can be adjusted to the position for optimum effectiveness withrespect to the upper slice lip and the bottom wall of the headbox in alladjusted positions of the slice lip.

It is particularly an object of the invention to provide a headbox asoutlined above wherein a novel construction and combination of the upperslice lip and a footwalk extending above the forming wire assuresmaximum rigidity of the slice lip in all its adjusted positions andminimum tendency for vibrations in the stock supply system to producevariations in the contour of the slice opening.

Additional objects and advantages of the invention will be apparent fromthe following description, the accom panying drawings and the appendedclaims.

In the drawings FIG. 1 is a somewhat diagrammatic view in verticalsection showing a headbox constructed in accordance with the invention;

FIG. 2 is a fragment of FIG. 1 showing a moved position of the upperslice lip and associated rectifier rolls;

FIG. 3 is an enlarged fragment of FIG. 1 showing details of the slicelip construction;

FIG. 4 is fragmentary and somewhat diagrammatic front view of theheadbox of FIG. 1;

PEG. 5 is a fragmentary side elevation of the headbox of FIGS. 1-4looking from right to left in FIG. 4;

FIG. 6 is an enlarged section on the line 6-6 of FIG. 5 showing detailsof the adjustable mounting for the lower rectifier roll; and

FIG. 7 is a section on the line 77 of FIG. 6.

Referring to the drawings, which illustrate a preferred embodiment ofthe present invention, the flow chamber of the headbox is defined by afront wall Iii, side walls 11 and 12, a bottom wall 13, and a wall 15which extends in a continuous curve from the front wall to form both thetop and back walls of the headbox. Bracing ribs 16 extend around asubstantial portion of the outside of the wall 15. The wall also isprovided at the top with a port 17 equipped with a sealing cover 18.

The front wall It includes the upper slice lip 20 which is secured as bybolts 21 to the lower edge of the wall 10 and cooperates with the lowerslice lip 22 at the front of the bottom wall 13 to define a slice outlet23 through which the stock is discharged onto the forming wire 24 as itpasses over the breast roll 25. The slice lip 20 is adjustablehorizontally as described in detail hereinafter, and it is adjustablevertically with the front wall 10, which is suspended for verticalsliding movement from the dome which forms a rigid framework extendingacross the front of the headbox above the front portion of the wall 15.More specifically, the wall it depends from the screw members 31 of aplurality of jacks 33 each of which is mounted by a bracket 34 on top ofthe dome 30. The drive shafts 35 for all of the jacks 33 are providedwith a common drive (not shown) such as a hand wheel or motor.

The inlet portion of the headbox through which the stock enters theinterior of the headbox includes a distribution chamber into which stockis delivered by a plurality of supply pipes 41 connected in spacedrelation across the back of the headbox. From the distribution chamber40, the stock flows upwardly through a narrow inlet throat 42, and theinlet passage 44 defined by walls 45 and 46 above the throat 42 divergesupwardly to form a venturi passage leading directly into the back of theheadbox. A rectifier roll d8 is mounted within the upper portion of theventuri passage 44 to quiet turbulence in the stock as it emerges fromthe throat 42 and flows upwardly into the interior of the headbox.

As shown, the headbox of the invention is totally enclosed in the topbut is designed to operate with an air space within its upper port andabove the level of stock flow therethrough, and a connection 50 isprovided in one of the side walls for attachment to a suitablycontrolled source of air pressure. A plurality of shower pipe 51 arealso provided in the top of the headbox for continuously showering thetop of the stock flowing through the box to minimize the possibility ofthe development of foam. The control system for regulating the stocklevel within the box and the air pressure may be constructed, forexample, as described in the copending application of Corbin, Moore andPearson, Serial No. 746,450 filed July 3, 1958 and assigned to the sameassignee as this application, which is a continuation in part thereof.Alternatively, manual controls for the stock supply and air pressure maybe provided in conjunction with a conventional air pressure gauge andsight glass in one side wall of the headbox.

The stock enters the back of the headbox with an upward flow and atrelatively high velocity when the paper machine is operated at highvolumes, and it is therefore necessary to operate with a substantiallevel of stock within the box in order to establish desired uniformityof flow conditions before the stock is discharged onto the forming wire.Since this in turn requires substantial deceleration of the flow rate,it is usually found necessary to provide rectifier means at anintermediate position in the box for the purpose of preventingfloculation or settling of the fibers as the stock flows toward thefront of the box. A single rectifier roll 55 of relatively largediameter, for example 24 inches, is shown in FIG. 1 for accomplishingthis result. It is also possible in the practice of the invention toemploy multiple rectifier rolls arranged in staggered, overlappedrelation as disclosed in the above Corbin et al. application.

It is also usually found necessary for optimum results to providerectifier means adjacent the slice outlet of a headbox for the purposeof subduing eddies which might otherwise cause non-uniform sheetformation. FIG. 1 shows a pair of rectifier rolls and 61 arranged forthis purpose, the roll 60 being positioned in closely spaced relationwith the bottom wall 13, and the roll (B 61 being positioned invertically spaced and overlapping relationship with the roll 61 and inclosely spaced relation with both the roll and with the upper slice lip20. It will also be noted that the spacing of the rolls 6t) and 61 isnon-uniform with respect to the outlet opening 23, and preferred resultsare obtained when the arrangement of the rolls is such that a planepassing between the rolls at right angles to the plane containing theiraxes will intersect the bottom slice lip at a location spacedsubstantially rearwardly from the slice opening 22.

Special provision is made in accordance with the invention forestablishing assured rigidity in the upper slice lip 20 while at thesame time making it possible to adjust the lower end of the slice lipgenerally horizontally. This is particularly important for a variety ofreasons. For example, any variation in absolute straightness andsmoothness of the discharge lip will be reflected in nonuniformformation of the sheet. In addition, any vibrations or pulsations in thestock supply system must be subdued to the maximum extent before thestock reaches the wire, and it is important from this standpoint to havemaximum assurance that the upper slice lip will not vibrate or otherwisebe subjected to deflection, especially non-uniform deflection, duringoperation of the machine.

The above objectives are accomplished in accordance with the inventionby a novel construction and combination of the upper slice lip 20 withthe footwalk 65 which extends across the front of the head-box above theforming wire. The footwalk itself comprises a trough-shaped section ofsheet metal of substantial rigidity, and it is provided with a hand rail66 extending along its forward side. The footwalk 65 is mounted on andrigidly secured to the front of the upper slice lip 20 by means of aplurality of generally L-shaped brackets 67 which are located inrelatively closely spaced relation across the full width of the headbox,satisfactory results have been obtained with these brackets spaced on 15inch centers. Additional rigidity is contributed to the slice slip by aplate 68 supported on the upper ends of the brackets 67 and weldedthereto and to the slice lip.

The plate 68 also serves as a support for the mechanism for adjustingthe extension member 70 which forms the lower edge of the slice lip 20.Referring particularly to FIG. 3, the extension member 70 extends thefull width of the slice lip 21? and is supported for vertical adjustmentthereon by means of a plurality of clamp blocks 71 each provided with aclamp screw 72. Each of the clamp blocks 71 is in turn controlled by anadjusting screw 75 depending from and controlled by an adjusting knob 77carried by the plate 68. This arrangement provides for adjustment ,ofthe lip extension '70 to a position of absolute straightness andparallelism with the lower slice lip 22 which is thereafter maintainedin all adjusted positions of the slice lip 2%.

As already noted, provision is made for horizontal adjustment of theslice lip 20, by causing it to pivot or warp about a thin section 80which extends across its full width near its upper edge or point ofattachment to the front wall 10. The means for causing this movementincludes a pair of turnbuckles 81, one at each side of the headbox. Asbest seen in FIG. 5, one end of the turnbuckle 81 is provided with apivotal mounting 82 on the side wall 11, and the other end of theturnbuckle is pivoted in a clevis bracket 83 secured to the underside ofthe footwalk 65. It will thus be apparent that adjustment of theturnbuckles 81 will cause the entire slice lip assembly, including thefootwalk 65 to move generally horizontally and thereby to swing thelower end of the slice lip forward and backward. Throughout all suchadjusting movement, the footwalk and its mounting brackets maintain therigidity of the It is important for optimum production that therectifier rolls 6t and 61 always be in the closest possible relationwith each other and with the bottom wall 13 and slice lip 21), in orderto minimize the delivery of unrectified stock to the outlet, but it isat the same time essential to prevent frictional contact therebetween.It is also important that the non-uniform spacing of these rolls fromthe outlet be maintained in all their adjusted positions. The inventionprovides special mounting means for achieving these results.

Referring particularly to FIGS. 57, each of the journals 88 of therectifier rolls 60 is mounted in a bearing bracket $11 having aneccentric bore 91 in which the journal 88 is rotatably supported by abushing 92. The outer end of the bracket is formed with a transverseslot 93 having an inner end face 94 surrounding the bore 91, and theouter end of this how is sealed by packing 95 and a gland 96 bolted tothe face 94. A flange mounting bracket 97 is bolted to the outer end ofthe bracket 90 to form an end cover therefor.

The bearing bracket 90 includes a cylindrical inner end portion 99 whichextends through a complementary bore in a base plate 100, and through acomplementary horizontal slot 101 in the side wall 11. The bracket 90 isnormally secured to the plate 100 by a pair of arcuate clamps 103, andwhen these clamps are loosened, the

bracket 90 can be rotated in the plate 161). Since the bore 91 iseccentric with respect to the bracket portion 99, such rotation willhave the effect of moving the journal $8 in an arcuate path and therebylocating the roll 6% in the desired closely spaced relation with thebottom wall 13.

The slot 101 in the side wall 11 permits horizontal movement of thebearing bracket 90 for horizontal adjustment of the roll 61). This slotis sealed on the inside of the wall 11 by a seal plate 105 secured as byscrews 106 to the inner end of the housing 90. The plate 100 carriesscrews 107 which can be threaded against the outer surface of areinforcing plate 108 on the side wall 11 to draw the seal plate 102tightly against the inner surface of the wall 11, and the screws 107 areloosened when it is desired to adjust the roll 60.

The horizontal movement of the bearing housing 90 is effected andcontrolled by an adjusting screw 110 which is secured to the bore plate100 at 111 and passes through a bore in the side wall reinforcing rib113. Look nuts 114 and 115 are operable alternately to move the screw110 and to secure it in moved position, and FIG. 5 shows a convenientmeans for measuring the movement of the roll as comprising a pointer 116carried by the movable bearing assembly and cooperating with a scale 117on the sidewall 11.

The mounting for each journal of the roll 61 includes a sliding bearinghousing 120 similar to the housing 90 except that the bore therein forthe roll journal is not eccentrically locatedbecause there is no reasonto change the vertical position of the roll 61. The horizontal movementof the housing 121) is effected similarly to that of the housing 90, bya screw 123, lock nuts 124 and 125, and a cooperating bracket 126secured to the side wall 11. Under normal conditions, the verticaladjustment of the roll 60 is made at the time of installation of thebox, and need not thereafter be changed. The roll 61 is adjustedhorizontally to close running relation with the slice lip 20 in eachadjusted position of the latter, and the roll 60 is then similarlyadjusted horizontally into the proper closely spaced relation with roll61.

While the forms of apparatus herein described constitute preferredembodiments of the invention, it is to be understood that the inventionis not limited to these precise forms of apparatus, and that changes maybe made therein without departing from the scope of the invention whichis defined in the appended claims.

What is claimed is:

1. A head box for a paper making machine comprising a pair of side wallscooperating with bottom and back Walls and with front wall means todefine a flow chamber, said front wall means including a front wallmember secured in rigid relation with said top wall and an upper slicelip of rigid construction carried by said front wall member in dependingrelation therewith and cooperating with said bottom Wall todefine aslice outlet from said chamber, said front wall means also including athin section extending horizontally thereacross and of substantiallyless thickness than said slice lip to provide for forward and backwardswinging movement of said slice lip while maintaining said lip in sealedrelation with said front wall member, means forming an inlet for stockat the back of said chamber to provide for generally horizontal flow ofthe stock toward said slice lip for discharge through said outlet, apair of rectifier rolls located adjacent said outlet in non-uniformlyspaced relation therewith and in closely spaced relation with each otherand with said bottom Wall and slice lip respectively, said thin wallsection being located at a higher level than said rectifier rolls, meansconnected between said slice lip and said side walls for moving saidslice lip forward and backward about said thin section, and meansmounting said rectifier rolls on said side walls for adjustmentsubstantially parallel with said bottom wall to maintain said spacedrelation thereof to each other and to said bottom wall and said slicelip in accordance with the moved position of said slice lip.

2. A head box for a paper making machine comprising a pair of side wallscooperating with bottom and back walls and with front wall means todefine a flow chamber, said front wall means including a front wallmember secured in rigid relation with said top wall and an upper slicelip carried by said front wall member in depending relation therewithand cooperating with said bottom wall to define a slice outlet from saidchamber, said front wall means also including a thin section extendinghorizontally thereacross and of substantially less thickness than saidslice lip to provide for forward and backward swinging movement of saidslice lip while maintaining said lip in sealed relation with said frontwall member, means forming an inlet for stock at the back of saidchamber to provide for generally horizontal flow of the stock towardsaid slice lip for discharge through said outlet, a pair of rectifierrolls located adjacent said outlet in non-uniformly spaced relationtherewith and in closely spaced relation with each other and with saidbottom wall and slice lip respectively, said thin wall section beinglocated at a higher level than said rectifier rolls, means connectedbetween said slice lip and said side walls for moving said slice lipforward and backward about said thin section, means mounting saidrectifier rolls on said side walls for adjustment'substantially parallelwith said bottom wall to maintain said spaced relation thereof to eachother and to said bottom wall and said slice lip in accordance with themoved position of said slice lip, a substantially rigid footwalkextending across the front of said head box, and bracket means securingsaid footwalk in bracing relation directly to said slice lip below saidthin section to maintain said slice lip rigidly braced in all adjustedpositions thereof.

3. A head box for a paper making machine comprising a pair of side wallscooperating with bottom and back walls and with front wall means todefine a iow chamber, said front wall means including a front wallmember secured in rigid relation with said top wall and an upper slicelip carried by said front wall member in depending relation therewithand cooperating with said bottom wall to define a slice outlet from saidchamber, said front wall means also including a thin section extendinghorizontally thereacross and of substantially less thickness than saidslice lip to provide for forward and backward swinging movement of saidslice lip while maintaining said lip in sealed relation with said frontwall member, means forming an inlet for stock at the back of saidchamber to provide for generally horizontal flow of the stock towardsaid slice lip for discharge through said outlet, rectifier roll meanslocated adjacent said outlet in closely spaced relation with said bottomwall and slice lip, said thin wall section being located at a higherlevel than said rectifier rolls, means connected between said slice lipand said side walls for moving said slice lip forward and backward aboutsaid thin section, a plurality of generally L- shaped brackets secureddirectly to said slice lip below said thin section in spaced relationacross said headbox with one arm portion of each thereof projectingforwardly from a position adjacent the lower edge of said slice lip toeffect vertical bracing of said slice lip, and a substantially rigidfootwalk extending across the front of said headbox .and directlysecured to said arms of all of said brackets for cooperation with saidbrackets to effect horizontal bracing of said slice lip.

4. A headbox as defined in claim 3 comprising a plate extending acrossthe front of said slice lip below said thin section and secured insupported relation on the upper end portions of said brackets, and aplurality of adjusting assemblies connected between said lip extensionand said plate for regulating the adjusted position of said lipextension on said slice lip.

References Cited in the file of this patent UNITED STATES PATENTS292,047 Recker Ian. 15, 1884 1,818,777 Aldrich et al Aug. 11, 19311,906,355 Bagley et al May 2, 1933 2,022,298 Neilson Nov. 26, 19352,186,761 Malkin Ian. 9, 1940 2,225,435 Kellett et al Dec. 17, 19402,351,656 Auten June 20, 1944 2,615,374 Malkin Oct. 28, 1952 2,747,471Corbin et a1. May 29, 1956 2,749,815 Stewart June 12, 1956 3,019,486Stinson Feb. 6, 1962 FOREIGN PATENTS 464,219 Canada Apr. 4, 1950

1. A HEAD BOX FOR A PAPER MAKING MACHINE COMPRISING A PAIR OF SIDE WALLSCOOPERATING WITH BOTTOM AND BACK WALLS AND WITH FRONT WALL MEANS TODEFINE A FLOW CHAMBER, SAID FRONT WALL MEANS INCLUDING A FRONT WALLMEMBER SECURED IN RIGID RELATION WITH SAID TOP WALL AND AN UPPER SLICELIP OF RIGID CONSTRUCTION CARRIED BY SAID FRONT WALL MEMBER IN DEPENDINGRELATION THEREWITH AND COOPERATING WITH SAID BOTTOM WALL TO DEFINE ASLICE OUTLET FROM SAID CHAMBER, SAID FRONT WALL MEANS ALSO INCLUDING ATHIN SECTION EXTENDING HORIZONTALLY THEREACROSS AND OF SUBSTANTIALLYLESS THICKNESS THAN SAID SLICE LIP TO PROVIDE FOR FORWARD AND BACKWARDSWINGING MOVEMENT OF SAID SLICE LIP WHILE MAINTAINING SAID LIP IN SEALEDRELATION WITH SAID FRONT WALL MEMBER, MEANS FORMING AN INLET FOR STOCKAT THE BACK OF SAID CHAMBER TO PROVIDE FOR GENERALLY HORIZONTAL FLOW OFTHE STOCK TOWARD SAID SLICE LIP FOR DISCHARGE THROUGH SAID OUTLET, APAIR OF RECTIFIER ROLLS LOCATED ADJACENT SAID OUTLET IN NON-UNIFORMLYSPACED RELATION THEREWITH AND IN CLOSELY SPACED RELATION WITH EACH OTHERAND WITH SAID BOTTOM WALL AND SLICE LIP RESPECTIVELY, SAID THIN WALLSECTION BEING LOCATED AT A HIGHER LEVEL THAN SAID RECTIFIER ROLLS, MEANSCONNECTED BETWEEN SAID SLICE LIP AND SAID SIDE WALLS FOR MOVING SAIDSLICE LIP FORWARD AND BACKWARD ABOUT SAID THIN SECTION, AND MEANSMOUNTING SAID RECTIFIER ROLLS ON SAID SIDE WALLS FOR ADJUSTMENTSUBSTANTIALLY PARALLEL WITH SAID BOTTOM WALL TO MAINTAIN SAID SPACEDRELATION THEREOF TO EACH OTHER AND TO SAID BOTTOM WALL AND SAID SLICELIP IN ACCORDANCE WITH THE MOVED POSITION OF SAID SLICE LIP.